While Amazon is not confirming any such project, it recently hired a former Microsoft executive, Charlie Kindel. Kindel headed up the Windows Phone application platform and developer relations, although his role at Amazon is still a mystery. The close proximity of Kindel's name with the Kindle product line has been hard for bloggers to overlook. He also blogged about his new job on April Fool's Day, saying "Part of the following is true."

Kindel's LinkedIn page says he is at Amazon as a "general troublemaker in the tech & mobile space ... hiring developers, program managers and product managers."

He could not be reached for further comment.

Just about all that's known about the reported smartphone is that it will have a 4.7-in. screen and run a custom version of Android, much like the Kindle Fire tablet.

Yankee Group analyst Boris Metodiev said on March 27 that he expects Amazon to sell a smartphone at a low price, with the hope of making money by selling digital content as it has with the Kindle Fire. Metodiev cited a report in DigiTimes that Amazon was developing a 4.7-inch smartphone that could be released in 2014.